Abstract Health disparities exist among segments of the population, including differences by gender, race/ethnicity, education or income, disability, geographic location, and sexual orientation. Increasing the number of underrepresented persons, including African Americans, Hispanics/Latinos, and Native Americans, disabled, and those from low income backgrounds, in science- and healthcare-related fields is critical to closing these gaps, in meeting the needs of our increasingly diverse society, and raising the cultural competence of all scientists and health practitioners. However, while minority interest in science matches or exceeds that of whites, individuals of color and from disadvantaged backgrounds are underrepresented in higher education, and in particular science education. Providing high school students with opportunities for exposure to scientific environments and mentorship from scientists is key in developing a passion for and sustained pursuit of education in the sciences. Such opportunities are especially critical in promoting science interest among youth of color. The goal of Stanford's High School Program in Biomedical and Health Sciences, as one of four high school programs within the NIH/NIDDK-funded Short-Term Research Experience Program for Underrepresented Persons (STEP-UP), is to increase the number of youth who are committed to and well- positioned for careers in the sciences. The STEP-UP program provides opportunities for high school students to develop critical thinking and educational skills within a supportive environment in which they have sustained relationships with adults (often university faculty, medical and graduate students, and postdoctoral fellows) as well as peers in the program. Priority is given to recruiting and accepting talented students from populations less represented in the biomedical and health sciences, including students of color, students from low socioeconomic backgrounds, and disabled students. In addition to focusing on improved academic skills, STEP-UP strives to facilitate the development of positive attitudes toward science, scientific skills, and positive relationships with peers and mentors. In STEP-UP, each high school student is paired with an adult scientific mentor, enabling students to obtain first-hand experience in a scientific environment. Students also participate in didactic seminars, tours, and other events aimed at increasing science and education success. Students have opportunities to continue during the academic year as well, through participating in webinars, research, and other mentoring experiences. Since 2007, Dr. Bonnie Halpern-Felsher has been the PI/Program Director for one of four coordinating sites for the high school STEP-UP program. We are applying to continue and expand our coordination of the high school STEP-UP program, and specifically to be one of the coordinating institutions to recruit students from the 48 contiguous United States. The specific aims of our STEP-UP program are to: (1) Recruit and retain 25 11th and 12th grade high school students less represented in the biomedical sciences, including individuals from underrepresented racial and ethnic groups, individuals from disadvantaged backgrounds, and individuals with disabilities. (2) Provide these students with an 8-10 week program and year-round opportunities that offer mentoring, opportunities for hands-on exposure to scientific research, and exposure to NIDDK-mission areas. (3) Help improve applications for successful college admission among youth who might otherwise have more limited educational choices. (4) Provide all mentors, including graduate and medical students, postdoctoral fellows, and faculty, with training in mentoring high school students through formal training and didactic mentoring experiences, thus providing a cadre of mentors well trained and prepared to encourage adolescents to enter the sciences. Providing opportunities for underrepresented groups of youth to enter the science pipeline will not only increase the number of youth from diverse backgrounds entering biomedical and health sciences, it will increase the number of diverse health care professions and scientists overall. Our STEP-UP program emphasizes partnerships and focuses on academic preparation, thereby playing a large role in creating the conditions for success and becoming crucial for addressing the complex problem of underrepresentation in the science and health professions.